
function curry (func) {
  return function curriedFn(...args) {
    // 判断实参和形参的个数
    if (args.length < func.length) {
      return function () {
        return curriedFn(...args.concat(Array.from(arguments)));
      }
    } else {
      return func(...args);
    }
  }
}

const curried = curry(function (a, b, c) {
  return a + b + c;
})

console.log(curried(1, 2, 3));
console.log(curried(1, 2)(3));
console.log(curried(1)(2, 3));
